Cyclone separators are often used when is desired to separate particulates from a gas stream. By design, the cyclone separator induces the gas stream to flow in a vortex fashion so that the particulates are thrown outwardly by centrifugal force against the sides of the separator. These particulates find their way to a collector bin or the like at the bottom of the cyclone. The gas, freed of the entrained particulates, is discharged through a vortex finder tube directed into the center of the vortex where the gas is substantially free of particulates.
It has been known to locate a cyclone separator within a larger processing vessel or the like. The gas and entrained particulates enter the vessel and, due to differential pressure, enter the cyclone separator disposed within the vessel which causes the gas stream to swirl in a vortex fashion to remove the particulates therefrom.
A problem with such arrangements according to the prior art is that, to keep production costs low, a simple opening is provided to the cyclone separator to receive the gas stream. Often the opening is located proximate the axis of the larger processing vessel. Upon entering the processing vessel, typically through a bottom inlet, the stream flows in and through the vessel before entering the cyclone, usually through a simple opening provided therefor. As the gas stream flows through the simple opening wake turbulents cause eddies to be formed at cyclone inlet. Where the particulates are of a sticky or tacky nature such as, for example, in oil shale processing, these eddies tend to result in the particulates being deposited and accumulating at the cyclone inlet. Gradually, as the eddies deposit more particulates the cyclone inlet constricts choking the gas flow into the cyclone and producing more turbulents and eddies which accelerate the particulate build-up. Choking of the gas flow into the cyclone also reduces the velocity of the vortex in the cyclone leading to inefficient particulate separation. Eventually, the process must be shut down or the vessel removed service to clear the cyclone inlet.